Presentation
Cough.
Patient Data
Age: 60 years
Gender: Male
From the case:
Hilum overlay sign
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Left-sided mass with "hilum overlay" sign, minimal left basilar atelectasis.
From the case:
Hilum overlay sign
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The red arrowheads show normal hilar structures visible through the mass (blue arrows).
From the case:
Hilum overlay sign
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Anterior mediastinal mass, dependent atelectasis.
Case Discussion
The right hilum is visible through the anterior mediastinal mass on the chest X-ray, a finding known as the "hilum overlay" sign. This sign indicates that the mass is either anterior or posterior to the hilum. If a mass is within the hilum, then the soft tissue density mass and the soft tissue density hilum are indistinguishable on X-ray, and the hilum is obscured.